In recent years, a head mount display is increasingly expected to be applied to a number of fields of, for example, manufacturing, a medical care, a game, or a daily life. As the technology utilizing the head mount display, AR (Augmented Reality) technology that displays virtual information superimposed with a real world, and a VR (Virtual Reality) technology that changes display information by matching with a user's motion are known, for example.
In the above-described AR technology and the VR technology, a self position estimation technology that estimates a position or a posture of a user is used. As the self position estimation technology, SLAM (Simultaneous Localization and Mapping) is known, for example. The SLAM is a technology that the self position estimation and an environmental map creation are performed at the same time. Patent Literatures 1 to 3 disclose the technology that the self position estimation is performed by the SLAM. By the SLAM, characteristic points are tracked using images captured from a moving object in time series, for example, thereby estimating a self position of the moving object.